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Artificial muscles robotic arm with full range of motion [video]

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Re: Artificial muscles robotic arm with full range of motion [video]

#32

A few comparisons: > forearm with hand [weighs] only 1 kg That is slightly below a human forearm with a hand. > This artificial muscles robotic arm is operated by water and consumes 200W at peak The ideal consumption necessary to raise this 7 kg dumbbell by 1 meter in 1 second is 7 watts. Human muscle is about 20% efficient, so it probably consumes about 35 watts. Almost a tenth the power. A human arm can also achiev…

>The ideal consumption necessary to raise this 7 kg dumbbell by 1 meter in 1 second is 7 watts.

You sure?

A HP is 75 Kg raised by 1 meter in 1 second (and is roughhy 750 W): https://en.wikipedia.org/wiki/Horsepower

Raising 1/10th of the weight by same distance in the same time should be 1/10th of that i.e. 70-75 W.

Re: Artificial muscles robotic arm with full range of motion [video]

#33
I've watched the video three times and I have my doubts.

Why is the robot arm a right arm and the one manipulating it a left arm?

Why is nothing above the elbow shown?

I am not saying this is fake, but it wouldn't be hard to fake. A few little zipping noises, some body paint, speed it up slightly, add in some CGI muscles underneath the skin...

Again, I'm not saying it is fake, but it could easily be. Extraordinary claims require extraordinary evidence.

Re: Artificial muscles robotic arm with full range of motion [video]

#35
post #33

I've watched the video three times and I have my doubts. Why is the robot arm a right arm and the one manipulating it a left arm? Why is nothing above the elbow shown? I am not saying this is fake, but it wouldn't be hard to fake. A few little zipping noises, some body paint, speed it up slightly, add in some CGI muscles underneath the skin... Again, I'm not saying it is fake, but it could easily be. Extraordinary cl…

>Why is the robot arm a right arm and the one manipulating it a left arm?

are you asking about the person manipulating it? If so I guess that person is just right handed and needs to hold the camera somehow...

Re: Artificial muscles robotic arm with full range of motion [video]

#36
post #33

I've watched the video three times and I have my doubts. Why is the robot arm a right arm and the one manipulating it a left arm? Why is nothing above the elbow shown? I am not saying this is fake, but it wouldn't be hard to fake. A few little zipping noises, some body paint, speed it up slightly, add in some CGI muscles underneath the skin... Again, I'm not saying it is fake, but it could easily be. Extraordinary cl…

Just check the other videos on the cannel. It gets pretty clear it's not a fake because you can see different stages and components that make it.

Re: Artificial muscles robotic arm with full range of motion [video]

#37
post #36
post #33

I've watched the video three times and I have my doubts. Why is the robot arm a right arm and the one manipulating it a left arm? Why is nothing above the elbow shown? I am not saying this is fake, but it wouldn't be hard to fake. A few little zipping noises, some body paint, speed it up slightly, add in some CGI muscles underneath the skin... Again, I'm not saying it is fake, but it could easily be. Extraordinary cl…

Just check the other videos on the cannel. It gets pretty clear it's not a fake because you can see different stages and components that make it.

I did as well, so I don't think it's fake now. It is still weird to me that the video uploaded was shot so poorly. The OP could use a tripod.

Re: Artificial muscles robotic arm with full range of motion [video]

#38
post #32

A few comparisons: > forearm with hand [weighs] only 1 kg That is slightly below a human forearm with a hand. > This artificial muscles robotic arm is operated by water and consumes 200W at peak The ideal consumption necessary to raise this 7 kg dumbbell by 1 meter in 1 second is 7 watts. Human muscle is about 20% efficient, so it probably consumes about 35 watts. Almost a tenth the power. A human arm can also achiev…

>The ideal consumption necessary to raise this 7 kg dumbbell by 1 meter in 1 second is 7 watts. You sure? A HP is 75 Kg raised by 1 meter in 1 second (and is roughhy 750 W): https://en.wikipedia.org/wiki/Horsepower Raising 1/10th of the weight by same distance in the same time should be 1/10th of that i.e. 70-75 W.

energy = force times distance

force = 7kg times 10N/kg = 70N (roughly)

So yes, more like 70W

Re: Artificial muscles robotic arm with full range of motion [video]

#39
post #10

This guy is a great engineer, I’ve been following his stuff for a while now. But there are unfortunately several fundamental limits which mean this type of system will likely never reach human level performance in a real world system. I work in robotics, specifically compliant and modular actuators, similar to the ones in the video. As I see it, (and many others in the field) One of the biggest issues in robotics is…

> In a nut shell, to make these strong enough to do much useful work, you need them to be really big, and that means they can’t move very fast.

Strength is additive. Why can't you just add more smaller muscle fibers that work in concert? That's basically how real muscles work. This seems so obvious there must be something wrong with the idea.

Re: Artificial muscles robotic arm with full range of motion [video]

#40
post #32

A few comparisons: > forearm with hand [weighs] only 1 kg That is slightly below a human forearm with a hand. > This artificial muscles robotic arm is operated by water and consumes 200W at peak The ideal consumption necessary to raise this 7 kg dumbbell by 1 meter in 1 second is 7 watts. Human muscle is about 20% efficient, so it probably consumes about 35 watts. Almost a tenth the power. A human arm can also achiev…

>The ideal consumption necessary to raise this 7 kg dumbbell by 1 meter in 1 second is 7 watts. You sure? A HP is 75 Kg raised by 1 meter in 1 second (and is roughhy 750 W): https://en.wikipedia.org/wiki/Horsepower Raising 1/10th of the weight by same distance in the same time should be 1/10th of that i.e. 70-75 W.

Yeah it is wrong. 68W ideal, assuming pure conversion to potential energy with no loss:

https://www.wolframalpha.com/input/?i=7kg*1m*%289.8m%2Fs%5E2...

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